Antifriction-roller



(No Model.)

1. H. RICHARDS. ANTIFRIGTION ROLLER.

No. 519,591. Patented May 8, 1894.

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UNITED STATES" PATENT OFF CE.

' ments. Fig. 2 is a side view, partially in sec -hereinafter more fully set forth.

a driven element or lever-arm, .G, which is ANTlFRlCTlO N-ROLLER.

SPECIFICATION forming part of Letters Patent No. 519,591, dated May 8, 94.

fA limibn filed SeptemberlZ. 1893. SerialNo. 485.318. (Nomodch) To all whom it may concern:

3e it known that I, F ANCIs H. RICHARDs,a citizen of the United States, residing at Hartford, 1n the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Antifriction-Rollers, of which the following is a'specification.

This invention relates to anti-friction roll ers of the class used in connection with cams and like machine-elements; the object being to furnlsh an anti-friction roller and means for supporting the same, whereby the roller shall be self-adjusting to the surface of the cam or arm operating in. connection therewith,- and which shall also be self-clearing, as

In the drawings accompanying and form ing a part of this specification, Figure 1 is a sectional plan view of a machine-element of the class specified, broken away on the line aa, Flg. 2, embodying my present improvetion, of the same. Fig. 3 isa longitudinal sectlon of the roller. Fig. at is a side view of the roller-pin. Fig. 5 is a view similar to a portion I of Fig. 1, illustrating the self=adjustment of the roller. Fig. dis a View illustrating a modificatlon of the device, omitting the self-ad-- gusting feature but retaining the self-clear-- Ingfeature thereof.

Similar characters designate like parts in all the figures. For the purpose of illustrating my present lnvention, I have, in the drawings, shown the cam rOIler and the supporting-pin thereforcarried by a rocker-arm, or'roller-carrier, A, supported upon a shaft, 2, and having the two arms, 3 and=4, in and near the ends of whlch the roller-bearing B is carried, in operative engagement with the cam-face, 5, of-

shown pivotally supported at 6. It is evi-. dent that if a reciprocatory movement be glven to the roll-carrying arm A, a modified reclprocatory movement will be imparted to the lever-arm C. i

According to my present improvementathe roller-pin'B, shown in detail in Fig. 4, has the middle portion, 7, thereof reduced in diameter, and bounded by oppositely disposed curved lines, so that, as seen in plan view in Figs. 1 and 4, said curved lines or sides, 8 and 9, of said rollerecarrying portion of the pin B, are oppositely-disposed circular arcs. In like manner, the bore, 10,-0f the roller D, is smallest in the middle portion of the length thereof, and increases toward each end on similar curved. lines, (8' and 9', Fig. 3) as shown in the sectional views of said roller,

Figs. 1 and 3. The result of this construction is that when the roller is placed on the rollerpin as in Fig. 1, (the length of the roller-being somewhat less than the space between said arms 3 and 4B,) the rolleris made self-adjusting, so that it will slide along on the bearing toward one or the other end thereof, to bring the face of the roller to an even bearing against the cam-face 5 of the roller-arm C.

This mode of self-adjustment will be understood by comparison of Figs. 1 and 5; in the latter. figure, the roller is shown carried toward oneend of its bearing, and consequently stands at a considerable angle, as illustrated in the drawings. By the means here described, the roller is made perfectly self-adjusting to the varying shape of the cam-face,

andshifts its position on said face so as to overcome even the slightest defects of workmanship and make the roller and said cam; face always hear properly throughout their width, during the entire stroke of the rollercarrier. The minimum diameter of the bore 10 of the'roller is made equal to or larger than the diameter of one end (usually the smallest end) of the roller-pin B,'so that said roller and the pin or bearing maybe assembled.

Another object of this considerable diiference' in said, diameters is to provide an open space at 11, between the back side of the roller pin and the, rearward inner surface of the roller, for the free passage of air and dust. This is for the purpose of preventing clogging of the roller by accumulation of dust when the improvement is used on weighing-machines in mills and granaries, where the atmosphere is heavily laden with floating particles.

When myimprovement .is'used in connection with the valve-mechanism of a' weighingmachine, for which purpose itis especially intended, and since said machines are, in

nearly all cases, used in' Very dusty rooms, it

is found that the dust will unavoidablyaccu- .mulate (when using ordinary rollers) in the space between the roller and its pin, thereby varying the amount of friction between the same and causing a variation in the working eflieiency of the machine itself.

By means of my present improvement, I not only secure the self-adjustment required, but the shape of the bore of the roller is such, that any dust lodging in the middle portion of said bore will, by the rotation of the roller, be gradually carried outward to the ends of the roller and there discharged; this mode of action follows the well-known principle of a conical bearing, in which, as is well known, the lubricating material is naturally carried toward the end of the bearing which is largest in diameter. By combining this feature with the construction whereby the roller is made self-adjusting, the roller is made both selfclearing and self-adjusting, and is found, in

practice, to be uniform in its action during long periods of time, without lubrication (other than by the dust of the rooms in which it is operated) and without any obstruction by accumulations of dust therein. This result has been obtained at the cost of much experiment, in which the efliciency and utility of the invention have been practically demonstrated, by the application thereof to the valve-mechanisms of numerous automatic weighing-machines of the class described in Letters Patent No. 442,859, dated December 16, 1890; the roller herein described is especially intended for use in place of the roller shown in that patent.

In practice, if the self-adj usting feature of the roller be not required, the lubricating and self-clearing feature thereof may be obtained by making the bore of the roller of least diameter in the middle portion of its length, in the form of truncated cones set point to point, as indicated, for instance, in Fig. 6. This form of the roller will, of course, require the roller-bearing to be of corresponding construction as there shown, it being of least diameter in the middle portion thereof and increasing in size on diverging lines as shown. As in the former case, the diameter of the bore of the roller is considerably larger, at any given point in the length thereof, than the diameter of the roller-bearing at said point, so as to give the same free passageway at 11 between the rearward side of the roller-bearing and the inner rearward face of the bore of the roller.

Having thus described my invention, I claim 1. In a machineelement of the class specified, the combination of a roller-bearing bounded by oppositely disposed curved lines, substantially as described, and of reduced diameter in the middle portion thereof, and a roller mounted on said bearing and having its bore shaped on corresponding curved lines and of reduced diameter in the middle portion of its length, but of greater diameter than. the said bearing, whereby the roller is self-adjusting on the bearing to the drivenelement of the device, substantially as described and for the purpose specified.

2. In a machine-element of the class specified, the combination of a roller-bearing of reduced diameter in the middle portion thereof and increasing in diameter from said middle portion toward the ends of the bearing on diverginglines, and a roller mounted on said bearing and having its bore shaped on corresponding diverging lines and of reduced diameter in the middle portion of its length, and having a free space, when the roller is in use, between one side of the bearing and the inner surface of the roller, the smallest diameter of said bore being equal to or larger than the diameter of one of the enlarged ends of said bearing, whereby the parts may be assembled, and whereby the roller is made self-clearing, substantially as described. 8 5

FRANCIS l-I. RICHARDS.

Witnesses:

JOHN L. EDWARDS, J r., FRED. J. DOLE. 

